Comcast Port 5060 / 69

Question

I have business class internet and am trying to setup a new VOIP system.

I need the following ports open for the system to work:

Ports needed to be opened:

UDP

69

5060

9000

20000-31000

32768-38000

TCP

3998

6800-6802

6880

7900-7999

We have a sonic wall and when the phones have not worked, we involved our hired IT guys. They attempted to open all of the ports directly from the sonic wall and had no luck. Once this occured, we tried for giggles to see if the ports were open when we connected directly to the comcast modem. They were blocked there too.. I have called Comcast Tech support and they say they are open. We went to level II and they said open up port forwarding... We switched modem to passthrough or bridge mode and attempted, still same thing.

I need these ports open for the phone to work and it seems that maybe they are being blocked upstream from our office somewhere... ANY IDEAS OR HELP would be great!

train_wreck · Answer

I have found the website http://canyouseeme.org a very good, quick and functional TCP port test.

I know that to the left of the port forwarding rules on my old SMC, there was a box you had to check that was labeled "Enable", otherwise the rule, even though it was showing up in the interface page, was not active.

I am assuming you have opened up the relevant ports Windows firewall (or Mac firewall if the laptop's a Mac)? And that there is a running program designed to receive traffic on those ports?

Also, if you have a static IP, you can try configuring your laptop with the requisite settings; the SMC should do absolutely no firewalling to static IP address devices.

I can assure you that Comcast is not blocking those ports; the ones listed here are the only ones they block http://businesshelp.comcast.com/help-and-support/internet/ports-blocked-by-business-class-internet/

jjones0421 · Answer

Thank you for your response.

So, we have attempted to see if it is on our network or on the comcast side. To do this, I plugged a laptop directly into the SMC modem, setup port forwarding to the assigned DHCP IP address of the laptop, and then ran the test that was provided by the phone system company. The link for the test is below:

https://lantest.broadviewnet.net/voiptest/simplicity?n_line=15

It still shows that TCP 5060; UDP 5060 and UDP 69 is being blocked, despite the setup in the modem and the port fowarding.

I also tried to see if the port was open by telnet the phone server with telnet Ip address 69 and it times out.

My biggest thing is before I do any more with our tech service, i need to make sure it is open on our end, with comcast.

Any ideas?

VBSSP-RICH · Answer

Hello jjones0421 and welcome,

You cannot put any industry modem into true bridge mode (tbm) and expect the staticIPs to still work because tbm always disables the modem's internal routing and only allows pass-through to work.

Okay, so if you are using a Sonic Firewall (SF), then you must have at least 1 Comcast staticIP and whether you VOIP is built-into the SF or if your VOIP system is using a different static IP, the process to open the Ports will be the same as follows:

1. log into your Comcast Gateway using browser to 10.1.10.1, username/password = cusadmin/highspeed.

2. If you are using an SMCD3G or NetGear3000, then go to firewall, click on Port Forwarding, then click on Static IP Port Managment ; or if you are using a DPC3939B , then go to Advanced, then static Port Forward and in all cases you will need to add the Ports you want to be opened on the specific Static Routable IP Address that is facilitating your VOIP system. On the Netgear 3000, you may have to enable the staticIP Port FW by unclicking the check mark before you receive the active blobk all port with the exception of the following ports. Always us this selection to maximize security and ONLY have the ports you need opened.

Hope this helps you out.

jjones0421

Comcast Port 5060 / 69

train_wreck

jjones0421

VBSSP-RICH